A user commonly retrieves information from online resources using a search engine, such as the Bing™ search engine provided by Microsoft Corporation of Redmond, Wash. In this approach, the user submits a search query that includes one or more key terms. The search engine responds by identifying and forwarding results that match the search query.
A user can also obtain information by interacting with one or more human contacts using a social network service. Well known examples of such services include Facebook, Inc. of Palo Alto, Calif., MySpace of Beverly Hills, Calif., and LinkedIn of Mountain View, Calif., etc. In this type of service, a user may create a profile and establish links to other users who also maintain profiles on the service. Yet another popular type of social network service is Twitter of San Francisco, Calif. In this type of service, a user can send short messages (i.e., “tweets”) to recipients (i.e., “followers”) who wish to receive these messages.
The above-mentioned types of social network services are predominantly used to provide information to recipient users who wish to receive it. But users sometimes use these services to actively pose questions. For example, a user can pose a question in the form of a status message in a user page provided by the Facebook service; or a user can send out a “tweet” that poses a question using the Twitter service. A friend or follower can manually reply to the question by posting a response to a status message or sending a response “tweet,” respectively.
Search engines and social network services have respective strengths and weaknesses as tools for answering a user's questions. In view thereof, some efforts have been made to combine features of search engines and social network services. Yet there remains room for improvement in such hybrid type of systems.